The subject invention is directed to the field of door blocking devices for preventing a door from moving from an open position to a fully closed position.
Many commercial establishments are provided with doors which permit employees and customers to readily exit from the establishment in case of emergency, such as, fire or other hazards in the establishment. While the front doors of commercial establishments such as retail shops, restaurants and the like are normally maintained in an unlocked condition during business hours, such establishments also frequently have other portals or doors in the rear of the establishment which are maintained in a closed and locked condition and which cannot be opened in a normal manner by persons in the area outside the door. However, it is essential that such doors be capable of being opened from inside the building for use in routine matters, such as, removable of trash. On such occasions, it is frequently desirable to maintain the door in an open non-closed condition for a short time to permit reentry of the user; however, the user frequently has his hands full and cannot manually hold the door in an open position and must spend an inordinate amount of time in effecting blockage of the door.
A wide variety of devices for holding doors in open position have consequently been proposed by those of skill in the art. However, the previously known devices have suffered from a number of shortcomings, such as, being overly complicated and consequently expensive and requiring the user to manually manipulate the closure preventing device in a variety of ways for deactivating the device to permit door closure following return of the user into the building. It is consequently sometimes difficult for a user returning to the building with a cumbersome item, such as, an empty trash container to easily and effective deactivate the door-stopping device while holding the door open against return to its closed position. Other devices require the provision of separate items, such as, brackets, keepers or the like, which must be attached to the door frame or floor for engagement with apparatus attached to the door so as to retain the door in a latched open position. Such devices consequently require substantial labor for installation and maintenance and also in some instances can create a safety hazard.
With respect to the prior art which is directed to devices requiring separate latches or the like attached to the door frame or the floor of the building adjacent to the door which cooperate with door mounted means for maintaining the door in an open position, it should be noted that U.S. Pat. Nos. 646,533; 759,013; 900,621; 1,493,794 and 3,620,483 all relate to devices employing cooperating means attached to the building or floor structure. Similarly, U.S. Pat. DES. 346,109 discloses a door spacer device apparently mounted on a door frame; however, the mechanical structure and operation is not apparent from the disclosure of such patent.
It should also be noted that latch devices for windows, cabinets and the like have been provided with a variety of rotary latch means for holding linear telescopically mounted members in axially adjusted position by use of rotary latches and the like, such as exemplified in U.S. Pat. Nos. 4,042,266; 4,331,355; 4,688,834; 4,709,949; 4,779,906; 4,790,580; 4,932,695 and 5,217,267 all relate to such telescopically mounted latchable devices. Prior art devices requiring separate manual manipulation for disengaging a door stop are exemplified by U.S. Pat. Nos. 1,921,568; 2,565,906; 3,287,050; 3,737,186; 3,809,419, 4,570,984; 4,686,740 and 5,123,685. Other devices such as exemplified by U.S. Pat. Nos. 4,925,072 employ means for latching a closure in position so that it can be reopened by pressure toward the closed position.
Therefore, it is the primary object of the preferred embodiment of the invention to provide a new and improved door blocking device for retaining a door or other closure in a non-closed position.
A further object of the present invention is a provision of a new and improved door blocking device which does not require any manual manipulation of the device for achieving deactivation of the device.
Yet another object of the present invention is the provision of a door blocking device which is deactivated solely by movement of the door toward a more open position from a closure preventing position.
Yet another object of the present invention is the provision of a reliable and economical door blocking device which is initially actuated by the user while opening the door so as to arm the device to preclude full door closure until such time as a further movement of the door toward the open condition is effected.
The preferred embodiment of the subject invention achieves the foregoing objects by the provision of a base member which is attached to an edge portion of the internal surface of an external access providing hinged door of a building. The base member supports a pivotal stop which can pivot between a first or deactivated stop position in which the pivotal stop is positioned within the periphery of the door and a second or extended activated stop position extending beyond the door periphery. The pivoted stop is spring biased towards its first or deactivated position but is prevented from returning to first or deactivated position by rotary latch until such time as the user initiates return to the building. The rotary latch is mounted on the pivotal stop and a series of pivotal movements of the pivotal stop brings the rotary latch into contact with a series of cam surfaces which rotate the rotary latch into a series of positions required during each cycle of operation of the invention.
A cycle of operation begins when a user opens the door and then manually moves the pivotal stop in an opening direction from its first or deactivated position to a second or extended activated position which results in contact of the rotary latch with a first positioning cam surface which rotates the latch into a second position. The user releases the pivotal stop which permits the spring biasing the pivotal stop to move the pivotal stop in a closing direction to an intermediate position in which the rotary latch engages additional positioning cam surfaces which position the latch so that it terminates the closing movement of the pivotal stop. The pivotal stop is consequently held in the intermediate position in which the pivotal stop extends beyond the periphery of the door. The user subsequently releases the door which swings towards its closed position by operation of conventional door closing apparatus. However, the pivotal stop engages the door jamb and prevents full closure of the door with such engagement resulting in pivotal movement of the pivotal stop back to its second or extended position while still preventing fall closure of the door.
The last-mentioned movement of the pivotal stop back to its second or extended position also results in contact of the pivotal stop with positioning cam surfaces in a return enable position where it remains until the user decides to return inside the building and manually opens the door. Opening of the door terminates contact of the pivotal stop with the door frame so that the spring bias effects a rapid return movement of the pivotal stop to its first position in which it is fully within the confines of the door periphery and does not interfere with full door closure being effected by the conventional door closing apparatus when the door is released by the user. During the last-mentioned movement of the pivotal stop, it passes through the intermediate position so that the rotary latch engages positioning cam surfaces which rotate the latch into its final position in which it is properly positioned for the next cycle of operation. It is significant that the user""s only contact with the pivotal stop is when he initially moves the stop to its second or extended activated position.